Wall Street Inits. refer to the three-letter abbreviations used to identify publicly traded companies on the New York Stock Exchange (NYSE). ASE stands for American Stock Exchange, which is a stock exchange located in New York City and owned by Intercontinental Exchange. LBO stands for Leveraged Buyout, which is a financial transaction in which a company is purchased with a combination of equity and debt. NYSE stands for New York Stock Exchange, which is the world's largest stock exchange by market capitalization.